Test 4 - Cardiac Flashcards
What are the key ions for Cardiac function?
Sodium: rapid influx
Potassium: leaves cells
Calcium: slow influx
What is the function of the ions Na/K?
Initiation of muscle contraction
What is the function of the ion Ca?
To strengthen contractility
What is the order of signals being sent by the heart?
SA Node
AV Node
Bundle of His
Right/Left Bundle Branches
What bpm can be stimulated by SA node function?
60 - 100 bpm
What bpm can be stimulated by AV node function?
40 - 60 bpm
What bpm can be stimulated infranodally (below the nodes)?
20 - 40 bpm
What do Beta-1 receptors target?
Increase HR and contractility
What do Beta-2 receptors target?
Bronchodilation
What do Alpha receptors target?
Vasoconstriction and increased contractility
no HR increase
What happens during the “P Wave?”
Atrial depolarization
What happens during the “QRS Complex?”
Ventricle depolarization
What happens during the “T Wave?”
Ventricular repolarization (rest)
What happens if a patient is shocked on a “T wave?”
Ventricular Dysrhythmias
Bradycardia: Causes
Athletes, during sleep, in response to vagal stimulus, inferior MI
What is Bradycardia a S/E of?
Beta Blockers Digoxin Calcium Channel Blockers Inferior MI Hypoxia
Bradycardia: Treatment
Only treat if symptomatic (get rid of cause)
Sequence: Atropine -> Pacemaker -> Dopamine -> Epi
Tachycardia: Causes
Physical activity, pain, stress, fear, hypoxemia, hyperthyroid, caffeine, ETOH, nicotine
Compensatory response to decreased CO or BP
Tx: treat cause
A Fib and A Flutter: increased risk
Increased risk of clots and stroke
A Fib and A Flutter: Treatment
-Reduce ventricular rate
Ca Channel Blocker, Amiodarone, Beta blockers, digoxin
-Cardioversion: onset <48 hrs prior
-Anticoagulants: onset >48 hrs prior
Check coag studies, TEE
Chronic A Fib Treatment
-Coumadin, Pradaxa, Xarelto
SVT/PSVT
No P wave
HR >150 bpm
Narrow QRS
SVT/PSVT: Causes
- Stress
- Caffeine
- Cocaine/ETOH abuse
- Rheumatic HD
- MI
SVT/PSVT: S/S
- SOB
- Chest tightness
- Palpitation
- Dizziness
- Hypotension
- Syncope
SVT/PSVT: Treatment
- Get rid of underlying cause
- “Bear down” = vagal stimulation
- Adenosine (Adenocard)
If unstable/symptomatic: immediate cardioversion
First Degree Heart Block: Treatment
Atropine
Mobitz I/Wenckebach: Treatment
Atropine if symptomatic
Mobitz II and Third Degree Heart Block: Treatment
Pacemaker
PVC: Treatment
- Eliminating contributing factors (i.e. stress and caffeine)
- Other factors: dig toxicity, hypoxia, HF, E-lyte imbalance (especially hypokalemia)
Meds: Amiodarone and Lidocaine
PVC: Care
Report increased frequency of PVCs
Stable (normal BP) V. Tach with Pulse: Treatment
- Notify HCP/Call a Rapid
- Amiodarone
Torsade’s V. Tach Tx: Mg
Unstable (low BP) V. Tach with Pulse: Treatment
- Cardioversion IMMEDIATELY
- Amiodarone
What causes Torsade’s de Pointes?
Low magnesium (<1.3)
V. Tach without a pulse
- CPR
- Defibrillation ASAP
- Epi
V. Fib Treatment Sequence
CPR
Defibrillate
Epi
V. Fib Meds
Epi: 1 mg q3-5 min
Amiodarone
Lidocaine
Magnesium Sulfate (if Torsade’s or low Mg)
Pulseless Electrical Activity Care
CPR
Treat causes
Epi
DO NOT SHOCK asystole or PEA
Causes of PEA: 6 H’s
Hypovolemia
Hypoxia
Hyper/Hypokalemia
Hyper: tx = glucose
Hypo: tx = K+ IVPB
Hyper/Hypothermia
Hydrogen ions (acidosis): tx = increase RR
HypoglycemiaCauses of PEA: 5 T’s
Tablets (drug OD): call poison control
Tamponade: pericardiocentesis
Tension pneumo: chest tube
Thrombosis (coronary and pulmonary): remove clot
MI: tx = cath labCardioversion vs. Defribrillation
Synchronized vs Unsynchronized
Sedation vs No Sedation
Cardioversion: needs a pulse
Cardioversion: Implications
Unstable A. Fib/Flutter
Unstable SVT
Unstable V. Tach
Defibrillation: Implications
Pulseless V. Tach
V. Fib
Where should the defibrillator pads be placed?
Top right - Bottom left
What are pacemakers used to treat?
2nd Degree (Type II )Blocks and 3rd Degree AV Blocks
Which side of the heart is paced?
Right side ONLY
What shows pacing is active on an EKG?
A spike before the P (atrial pacing) and/or a spike before the QRS (ventricular pacing)
Invasive Pacer: Complications
Infection/hematoma PVCs Under Sensing Failure to Capture Failure to Discharge
What happens in “Under Sensing”?
pacer doesn’t recognize a normal heart rhythm and paces anyway
What happens in “Failure to Capture”?
Pacer attempts to pace, but no QRS is formed
What happens in “Failure to Discharge”?
The pacer does not deliver a stimulus to the heart
Pacemaker: Pre-op Care
- Consent signed
- NPO (start IV for emergency meds if needed and for abx)
- Local anesthetic
Procedure in cath lab or OR
What conditions are included in Acute Coronary Syndrome (ACS)?
Unstable angina
Non-ST Elevation MI (NSTEMI)
ST Elevation MI (STEMI)
What causes Angina Pectoris?
Temporary imbalance b/w O2 supply and cardiac demand
Stable Angina: Characteristics
Predictable pattern
Relieved by rest and/or a little Nitro
Unstable Angina: Characteristics
More intense pain S/S at rest Poorly relieved by rest or Nitro May have ST depression No Troponin or CKMB changes
Increased MI risk
Variant (Prinzmetal’s) Angina: Cause
Due to coronary vasospasm (cold, stress, meds, smoking, or cocaine)
Variant Angina: Characteristics
- Occurs at rest and at the same time daily (midnight - 8am)
- Responds well to nitro and Ca Channel Blockers
Lower MI risk than unstable angina
Myocardial Infarction (MI)
The heart muscle is severely deprived of oxygen
Blood flow dropped by 80 % - 90%
Which is worse? STEMI or NSTEMI
STEMI: complete occlusion of a coronary vessel
MI: Risk Factors
- Age (>65)
- Elderly: s/s = generalized weakness, stroke, syncope, change in mental status
- Low estrogen
- Family hx of CAD
- Smoking
- High cholesterol
- Sedentary lifestyle
- Diabetes
- HTN
- Obese
Metabolic Syndrome: Risk Factors
- HTN: BP>130/85
- High Triglycerides: >150
- High Fasting BG: >110
- Large Waist: >40” males, >35” females
Women Heart Disease S/S
Atypical Symptoms:
- Abd pain
- Pain b/w shoulder blades
- Neck pain
More likely to have non-STEMI than men
Process of Infarction: General
E-lyte imbalance and acidosis = change in conduction and contractility
Increased Epi/NorEpi = increased O2 demand and cardiac workload
Process of Infarction: EKG Changes
1st) T Wave Inversion (ST depression)
2nd) ST Elevation (ACT FAST to prevent muscle injury)
3rd) Q Wave formation (necrosis = Q wave doesn’t resolve)
Which side of the heart has the AV and SA nodes?
Right side
What causes Bradycardia?
Inferior MI
What is occluded in an Inferior MI?
RCA (affects the SA and AV nodes)
II, III, AVF
What can Inferior MI cause?
Bradycardias and AV blocks
What is the main sign of an Inferior MI?
JVD
What is occluded in an Anterior or Septal MI?
LAD
V1-V6
Which has a higher mortality? Anterior/Septal or Inferior MI
Anterior/Septal MI
What can Anterior/Septal MI cause?
Ventricular dysrhythmia (V tach/V fib)
What is the function of an intra-aortic balloon pump?
To reduce the cardiac workload
What can cause JVD?
Inferior MI or Tricuspid issues
MI: S/S
-Pain/Discomfort in jaw, back, shoulder/abd
>30 mins
Common:
-N/V
-Diaphoresis (sweating)
-Dyspnea
-Anxiety
-Fever (as high as 102)
-New A. Fib onsetChest Pain Assessment: Acronym
PQRST
P: Precipitate (what happens before the pain?) Q: Quality R: Radiates (pain) S: Severity T: Timing (when, previous episodes?)
Cardiac Enzymes: MI
Troponin and CKMB Increase
ACS Interventions: Goals
- Relieve pain
- Stabilize hemodynamics
- Restore perfusion (get pt. to cath lab <90 minutes)
ACS Emergency Interventions
-ABC, defibrillate (V. Fib, V. Tach, No pulse)
-O2 if sat <90%
-Continuous EKG, VS, IV
-ASA as ordered (anti-platelets)
Give rectally if N/V
S/E to monitor:
-Bleeding
-Tinnitus (ASA toxicity symptom)
ACS Pain Relief
NTG (Nitro)
-if BP >90, HR 50-100
-not if “phosphodiesterase inhibitors” in past 24-48
ED meds = drastic BP fall
Morphine Sulfate (if pain doesn’t respond to NTG)
Morphine Sulfate: Implications
Given to reduce pain and cause vasodilation
S/E: RR depression, vomiting, hypotension
Narcan if OD
Fluids if hypotension
Chest Pain Treatment Acronym
MONA
M: morphine
O: oxygen (if <90%)
N: nitro
A: aspirin
Reperfusion Strategies Post-MI
PCI (best option)
-must be <90 min since onset
Thrombolytics (“-ase”)
- Give if onset <12 hrs - Door to needle <30 min
Over 12 hrs, revert to PCI
Fibrinolytic: Contraindications
- Symptoms suspected of aortic dissection
- Active bleeding (not menses)
- Any prior brain bleeds or known brain lesions
- Significant closed head trauma in past 3 months
Fibrinolytic: Post-Care
- Clotting studies
- Neuro assessment
- Check stools, urine, and emesis for blood
- Check IV patency
- Monitor for S/S of reperfusion
S/S of Reperfusion
- No pain
- Sudden burst (non-sustained) V. Tach
- ST segment normalized
MI: Complications
-Lethal dysrhythmias in 1st hr
V. Tach or V. Fib = common COD
PVCs
-Pericarditis
1 to 12 weeks post MI
-Septal Wall Rupture
DEADLY!
Rare
-HF
MI Complication: Right HF (RCA infarct)
- admin fluids
- Beware of volume depleting drugs
Must maintain preload to manage BP and CO
MI Complication: Left HF (LAD infarct)
- Diuretics
- Vasodilators
- Inotropics
MI Complication: Cardiogenic Shock
Left ventricle damage >40%
Mortality 65-100%
S/S: tachycardia, hypotension, pulmonary congestion, low UOP, cold/clammy skin, severe chest pain
Tx: stabilize with intra-aortic balloon pump (decrease workload of heart)
Intra-Aortic Balloon Pump (IABP)
Inflates: diastole (heart relaxes)
Deflates: systole (heart contracts)
Reduces cardiac workload
MI: Teaching
- Risk factor modification
- Activity
- Diet (low fat, cholesterol, and Na)
- Meds
- Follow up appointments
- VS (take own pulse)
- Sex (can walk up stairs w/o angina)
CABG: Post-Op Care
- Fluid/E-lyte balance (Potassium**)
- Maintain CO, VS, and temp
- Pain management
- Extubate as soon as stable
- Neurovascular Assessment
- Monitor Chest Tube output
Potassium Normal Levels
3.5 - 5.0
Normal UOP
1 mL/hr/kg or 30 mL/hr
What does a sudden cessation of Chest Tube Drainage mean?
Clotting (can lead to cardiac tamponade!)
Cardiac Tamponade: S/S
- JVD, clear lungs*
- Diminished heart sounds*
- Tachycardia
- Hypotension*
- Pulsus Paradoxus (BP drop with inspiration)
Heparin Induced Thrombocytopenia and Thrombosis (HITT)
- Low platelets
- Immune response to Heparin = antibodies forming a clot in vessel walls
HITT: Risk Factors
- Onset 5 to 10 days after Heparin initiation
- Female
- Higher incidence in post surgical
HITT: Clinical Manifestation
Plt: <100,000 or 50% of baseline*
Thrombus Formation: DVT (50%), PE (25%), Stroke, Death
Platelets: Normal Value
150,000 - 400,000
Spontaneous Bleeding Plt Level
<20,000
HIT: Management
-CBC: to monitor plt level
-DC all heparin meds (“-parin”)
i.e. Lovenox (enoxaparin)
-Use alternative anti-coags
Factor Xa
Warfarin
Post-CABG: Activity
- No lifting >15 lbs
- No driving, lifting, pulling for 6 weeks
- Activity as tolerated (rehab potentially)
- May resume sex: when can walk 1 block or 2 flights of stairs w/o SOB
Post-CABG: Report
- Red Incision
- Swollen/area around incision feels warm
- Drainage
- Fever >100.5
- Unusual chest pain, SOB, S/S of before surgery
- Daily weight: alert if gain of 6 lbs in 2 days
What is Heart Failure?
Pump failure = inability to maintain adequate CO
HF: Types
Left Sided
Right Sided
High Output
Left CHF (Congestive Heart Failure)
Can’t contract during systole
Can’t relax during diastole
Etiology: HTN, MI, Structural damage (valve issue)
Left CHF: affected valves/potential cause
Mitral & Aortic
Anterior MI
Right CHF: affected valves/potential cause
Tricuspid & Pulmonic
Inferior MI
Left CHF: S/S
- Dyspnea
- Pulmonary issues
- Decreased CO
- Extra heart sounds/heart gallop
May lead to R. HF
Right HF: Etiology
Most Commonly - CHF (L. HF)
Right HF: S/S
- Systemic Congestion
- JVD
Why do you give ACE Inhibitors post-MI?
To prevent hypertrophic remodeling
SNS Compensatory Reaction
Increase HR
RAAS Compensatory Reaction
Increase volume/Decrease UOP
Neurohormonal Response to HF
Endothelin (vasoconstrictor) = worsened HF s/s
BNP (vasodilator and diuretic)
What does high BNP indicate?
Heart Failure
High BNP Treatment
Lasix
HF: Diagnostics
- Chest X-ray
- ECG
- BNP Level (>90)
Hemodynamic Monitoring
Wedge Pressure: Left
CVP: Right
Lowered = Low CO
CO: Normal Value
4 - 8 L/min
RA/CVP: Normal Value
2 - 6 mmHg
PCWP (Wedge): Normal Value
8 - 12 mmHg
SVR: Normal Value
800 - 1,400
High = vasoconstriction Low = vasodilation
HF Treatment:
- Increased Preload
- Increased Afterload
- Decreased Contractility
Preload: give diuretic
Afterload: give morphine and Nitrates
Contractility: give Dobutamine
HF Treatment Goals
- S/S relief
- Increased exercise capacity
- Improve survival
- Meds as ordered
HF in Older Adults: Considerations
No NSAIDS!
Can exacerbate HF
Can cause H2O and NA retention
Pulmonary Edema
Severe S/E of L. HF (CHF)
Fluid leaks into the lungs, airways, and tissues
Pulmonary Edema: S/S
- Sudden onset
- Crackles
- Disorientation
- Extremely Anxious/Restless
- Struggling for air
- Moist, pink, frothy sputum
- Tachycardia
- Hyper/Hypotension
Pulmonary Edema: Management
- Airway (possible intubation)
- High Fowler’s
- Morphine
- Nitro
- Diuretics
- Dobutamine
When to stop activity with HF?
BP change of >20 mmHg
HR increase of >20 bpm
Heart Transplant Criteria
- Life expectancy <1 yr w/o transplant
- Age <65 (or very healthy)
- No infection, alcohol, or drug use
Orthotopic Heart Transplant
- Part of Original Atria left
- Vagus nerve is severed (atropine doesn’t work anymore)
- 2 unrelated P waves
Heart Transplant: Post-op Care
-Denervated heart unresponsive to vagal stimulation
-Responds slowly to stress, exercise, position changes
May need a pacemaker
Worsening HF: S/S
Call HCP if:
- Rapid weight gain
- Decrease in activity tolerance
- Excessive nocturia
- Orthopnea, dyspnea, or chest pain at rest (can’t lie flat anymore)
- Increased edema
Sleep Apnea
Directly related to CAD d/t diminishedO2 during apnea episodes
Tx: CPAP (improves CO and EF by decreasing preload, afterload, and BP)
Pacemaker Post-op Teaching
- Report S/S of pre-pacer
- Don’t stand too close to microwave when using
- No scanner at airport
- Avoid electromagnetic fields
ICD Teaching
- Report to HCP if it has to cardiovert (fires)
- Family needs to learn CPR in case cardiovert stops the heart
